The catalytic oxidative cyclocondensation of the o-aminophenols 1a-f was investigated. The oxidants used were air/laccase, H2O2/horseradish peroxidase, H2O2/ebselen (3), and TBHP/diphenyl diselenide 4. The products obtained were 2-amino-3H-phenoxazin-3-one-questiomycin A, its derivative 2b, and cinnabarinic acid and actinocin (2c,d). Substrates with methyl groups at 4 and 5 positions of benzene ring were converted to different dihydrophenoxazinones 2g,h. Compounds having chlorine atoms at the same positions underwent oxidation to planar phenoxazinones 2e,f with elimination of one hydrochloride molecule.
TEMPO-catalyzed electrochemical dehydrogenative cyclocondensation of <i>o</i>-aminophenols: synthesis of aminophenoxazinones as antiproliferative agents
作者:Jianmin Zhou、Zhi-Yuan Ma、Chantale Shonhe、Su-Hui Ji、Yun-Rui Cai
DOI:10.1039/d1gc02908h
日期:——
A TEMPO-catalyzed electrochemical synthesis of aminophenoxazinone through dehydrogenative dimerization with hydrogen evolution was developed.